Incubators for hatching eggs are known in which there is provided a heating means such as an electric element, for example that in a light bulb, and in which the air heated by the heating means passes upwardly around the eggs so as to warm eggs. This, however, is somewhat unnatural because in a nest the bird sits on the eggs and in nature heat is transmitted downwardly through the bird's plumage by conduction to the eggs.
It is also known to rotate eggs periodically, as it is considered desirable to prevent the developing embryo from sticking to the membrane within the egg. One known method for turning the eggs is to put a cross on one side of the egg and a circle on the other side of the egg and for the eggs to be turned by hand periodically. This is particularly laborious. In a known mechanical device for turning eggs, the eggs are put into a rack with their major axes vertical. The eggs are securely clamped in the rack and from time to time, for instance every quarter of an hour or every four hours, the rack is rotated through 90.degree. about a horizontal axis.
Whilst such a device gives tolerable results with the eggs of a reasonably domesticated birds, such as chickens and ducks, this device when used with the eggs of less domesticated birds, such as pheasants and geese, gives results which leave considerable room for improvement.
There is thus a need for an incubator which, by reproducing the effects found in nature, will give satisfactory hatching results.